When I wrote about PRH and its AI warning, I mentioned that I had personally seen one of the big five publishers hold up a book because a creator demanded a clause in their contract saying their work wouldn't be used to train an AI.
There's a good reason you'd want this in your contract; the standard contracting language contains bizarrely overreaching language seeking "rights in all media now know and yet to be devised throughout the universe":
https://pluralistic.net/2022/06/19/reasonable-agreement/
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